Call of Duty: World at War
The Arisaka makes its first and only appearance in Shi No Numa, where it can be bought off the wall in the starting room. Like the Kar98k, the Arisaka is great for headshots, and can maintain zombies for about 4 or 5 rounds. It is not available from the Mystery Box.
Through console commands, the Arisaka can be obtained in Der Riese, and can be Pack-a-Punched. It's name is "The Eviscerator," which was also supposed to appear in Der Riese but was cut.
Call of Duty: Black Ops
The Arisaka returned in the revamped Shi No Numa in the Hardened/Prestige Black Ops editions as well as the Rezurrection map pack. It retains many of its old traits.